<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
		<style>
			/*用户没点过*/
			a:link{
				color.red;
			}
			/*点过了*/
			a:visited{
				color:orange
			}
			/*鼠标悬停状态*/
			a:hover{
				color: aquamarine;
			}
			/*鼠标点击不松手*/
			a:active{
				color: black;
			}
		</style>
	</head>
	<body>
		<a href="https://www.baidu.com/">伪类</a>
	</body>
</html>
